So once I figured out my problems with installing Rails 3 on Debian Squeeze I ran into trouble installing the pg gem.
Again after trial and error I found that all I needed to install was the libpq-dev package.
apt-get install libpq-dev
gem install pg
This wasn’t as easy as I thought it would be, but after a little experimentation I got it running.
apt-get install ruby1.9.2
This will say that it is installing 1.9.1 but if you run ruby -v it will say 1.9.2
Then to install rubygems download and extract and then run
ruby setup.rb
To install rails run
gem install rails
Here is a great article on installing and using rvm.
CC=/usr/bin/gcc-4.2 rvm install 1.8.7
A great article about this can be found here: Lion, RVM, and Ruby 1.8.7 woes
Backup:
pg_dump -Fc dbname > dbname.dmp
Restore:
pg_restore -Fc -d dbname dbname.dmp